This invention relates to a process and a plant for improving any type of residual fuel derived from petroleum crude.
Residual fuels presently used suffer from the disadvantages of high viscosity, a sulphur content over 1.5% by weight, and have a maximum calorific value of 10,000 to 10,200 kilocalories per kilogram.
Residual oils of petroleum crude in general have the following characteristics.
______________________________________ Density at 15.degree. C 0.900 (min.) Flash point 70.degree. C (min.) Viscosity in .degree. E at 20.degree. C 180 (max.) Viscosity in .degree. E at 50.degree. C 20 (max.) Sulphur % 3 (max.) Ash % 0.2 (max.) Water and sediments % 1.0 (max.) Maximum calorific value kcal/kg 10,000 Coke 8 (max.) The fuels have the following approximate percentage composition: Carbon 84-87% Hydrogen 12-14% Sulphur 0.5-4: (according to origin) Vanadium 70 ppm. Nickel 30.5 ppm. ______________________________________
Considering the low quality of residual fuels derived from the distillation of petroleum crude of any origin, and the consequences which this has where the control of pollution is considered, and further considering the interest which exists in economising fuel of every type, it is clearly desirable to obtain combustible oils with the lowest possible sulphur content, the lowest possible viscosity at a given temperature, and the highest possible calorific value, that is to obtain a greater number of therms per kilogram of fuel than at present.
It must be stated that up to the present time, although applications for the distillation residue of petroleum crude have been sought and found, there has been no attempt to improve these residues.